Pneumatic ice tray and cube release



July 30, 1946. l.. L. MALLARD 2,404,972

PNEUMATIC ICE TRAY AND CUBE RELEASE Filed Dec. 4, 1941 Fm. '2 y HG2,

Patented July 30, 1946 UNITED STATES PATENT :OFFICE PNEUMATIC ICE TRAY AND CUBE RELEASE Logan L. Mallard, Norfolk, Va.

Application December 4, 1941, Serial No. 421,646

11 Claims.

This invention relates to refrigeration and more particularly to the freezing unit and trays associated therewith in which water or other matter is placed for freezing or congelation.

Removing an ice tray from the support upon which it is frozen and removal of cubes from the tray has been a recognized problem and numerous attempts have been made toward a solu tion of this problem. The present invention is directed likewise to a solution of this problem above stated, it being an object of the invention to provide (l) an improved means for breaking the ice bond between a tray and its support so that the tray may be easily removed from the cooling unit, and (2) also improved means for freeing the cubes from the tray after the tray is removed so that the cubes may be readily accessible for use.

The present invention utilizes fluid pressure means for freeing the tray from the support to which it is frozen and for freeing the cubes from the Walls of the cells of the tray in which they are formed. An expansible diaphragm or other member movable under the influence of fluid pressure is located between a portion of the tray and its supporting shelf, and this member is operated by fluid pressure supplied thereto by some suitable means, such as for example as by a manually operated pump. The ice tray is provided with a pressure area or chamber and the bottom of each ice cube cell is movable or flexible to facilitate removal of the ice cubes. The tray is` also provided with a valve inlet so that compressed air or other fluid may be introduced into said area or chamber to flex the bottoms of the cells and free ice cubes therefrom. The construction is such that the compressed air or other fluid pressure for freeing the cubes may be supplied from the same source as that for freeing the tray from its support.

The foregoing and other objects and advantages of the invention will become apparent in view of the following description taken in conjunction with the drawing, wherein:

Fig. 1 is a front elevation of a refrigerator embodying the invention, the refrigerator door being broken away to reveal the evaporator and coacting tray dislodging means;

Fig. 2, an enlarged section taken substantially on the line 2--2, Fig. 1;

Fig. 3, an enlarged view of a portion of Fig. 2 showing the tray dislodging means in operation;

Fig. 4, an enlarged fragmentary sectional elevation of the evaporator and adjacent Wall portion of the refrigerator with a tray in position to have its cubes released;

Fig. 4a is a fragment of the tray of Fig. 4 showing the flexible bottom or diaphragm of one of the grid compartments in normal freezing position;

Figs. 5 and 6, respectively, enlarged detail sectional views of a pneumatic bellows or foot pump and air-release nozzle.

As shown on the drawing a refrigerator cabinet I0 of conventional construction is provided with a door II affording access to the food compartn ment I2. Within the food compartment is located a refrigerating unit I3 having shelves I4 between which are a series of compartments I5 adapted to receive trays I6 for containing matter to be frozen or congealed.

A tray releasing member I'l is associated with one or more of the shelves I4 in a position to engage the tray for breaking the ice bond between the tray and the shelf thereby freeing the tray from the shelf after its contents have been frozen. This tray releasing member is preferably expansible or inflatable and as shown is a metallic envelope or diaphragm of thin metal which may be of good heat conducting properties to provide maximum heat transfer, although the same is not necessary. Means is provided for accommodating this tray freeing member, and accordingly for the purpose of illustration although not in a restrictive sense, the tray is provided with a recess or depression I 8 to receive the releasing element I l as shown particularly in Figs. 2 and 3.

The tray release II is preferably of a size commensurate with the tray to be used and is adapted to be inflated by air or other fluid from any desired source, as for example, a foot pump 2i) mounted in the vicinity of the base of the cabinet to be readily accessible for foot operation. The pump 20 consists of a cylinder having a piston 2l rcciprocable therein maintained in its upper position by means of a spring 22. A foot lever 23 is provided with a pedal 23', said lever being pivoted at its one end to a bracket 24 and at an intermediate point being slidably or movably connected to the stem of piston 2|, note Fig. 5. A tube 25 connects at its one end to the pump chamber and leads upwardly and is provided with a series of branch connections 26 which are connected to their respective expansible tray-releasing members I'I.

Figs. l and 2 show the ice cube trays in normal freezing position with the expansible tray-releasing members II lying flat in their respective recesses I9 on the shelves I4 of the evaporator,

while Fig. 3 shows one of the members l'l expanded to break the ice bond between a tray and the shelf on which it rests. In this manner, one or more trays may be dislodged by simply manipulating the foot, leaving the hands free to remove the trays or for other purposes.

To dislodge ice cubes from the grid sections of the respective freezing trays, the bottom of each grid compartment is provided with a flexible diaphragm 2l and beneath the series of grid co.. partments is a hollow air-pressure chamber 23, note Fig. 4. At its one end the tray is provided with a socket 29 having projecting from the center thereof a push rod or stem 29. A branch tube 30 connects into the air-pressure system at the upper end of tube 25 and projects outwardly through the adjacent wall of the cabinet. A valve cage or nozzle 3l is connected to the outer end of the branch tube 30 and has therein a Valve in the form of a ball 32 which is spring-pressed against its seat at the front or outer end of the cage, the latter being provided with an exterior flexible sealing gasket 33 to prevent leakage of air when engaging the socket 29.

When it is desired to dislodge ice cubes from the grid compartments of any of the trays I8, it is only necessary to press the socket 29 of the tray against the valve cage 32, thereby causing stem 29 to unseat the ball valve 32 and permitting air to be injected into the air chamber 28 and act on the expansible diaphragms 21 by simply manipulating thefoot pedal 23. When pressure is relieved from chamber 28, the diaphragm 2l exes downwardly against the bottom wall of the tray, as illustrated in Fig. 4a, making contact for good thermal conductivity.

From the foregoing, it will be seen that any one or more of the evaporator trays may be readily dislodged from thev evaporator shell and for ice cubes dislodged from the grid compartments of the tray by asimple manipulation of the foot, leaving the hands free to handle the trays.

It will. be understood that certain limited changes in construction and design may be adopted without departing from the spirit and scope of the invention as defined in the appended claims.

What is claimed is:

i. In a refrigerator having an evaporator provided with a freezing compartment, a shelf in said compartment, a tray removably disposed on said shelf, a hollow expansible member interposed between said tray and shelf, foot actuated hy draulic means providing a source of fluid under pressure, a conduit communicating said hydraulic means with said expansible member and whereby upon actuation of said hydraulic means fluid under pressure is injected into said expansible member to dislodge the tray from said shelf.

2. In a refrigerator having a food compartment and an evaporator disposed in heat transfer relationship with `respect to said food compartment, said evaporator being provided with a freezing compartment, a shelf in said freezing compartment, a tray removably disposed on said shelf, a hollow expansible member positioned between said shelf and tray, a source of uid under pressure including a foot-actuated hydraulic pump having a pressure chamber, a conduit communicating said pressure chamber with said expansible member and whereby when said pump is operated fluid under pressure is injected into said expansible member to dislodge the tray from said shelf.

3. In a refrigerator having a food compartment,

freezing compartment, a tray removably disposed in said freezing compartment, a wall on which said tray rests, said wall having a depression formed therein, a hollow expansible member disposed in said depression, a source of fluid under pressure, and a conduit communicating said source with said expansible member whereby upon injection of fluid under pressure into said member the ice bond is broken between said tray and wall.

5. A freezing tray to be disposed in the evaporator of a domestic refrigerator having a plurality of compartments for the fluid to be congealed or frozen provided with flexible bottoms constituting diaphragms, the base of said tray being formed with a hollow pressure chamber in communication with said diaphragms, said tray also having a nozzle with an opening therethrough communicating with said pressure chamber and a valve unseating member in said nozzle.

6. A metal freezing tray for use in the evaporator of a domestic refrigerator comprising a plurality of compartments for the fluid to be frozen each having the bottom wall thereof provided with a flexible diaphragm, said tray also having a pressure chamber and a socket forming part of a detachable coupling having an opening therein communicating with said chamber to permit introduction ef fluid under pressure thereto to flex said diaphragme and dislodge frozen matter from said compartments.

'7. In a refrigerator, a cooling unit having a freezing surface, a tray removably disposed on said surface, expansible means between said surface and said tray constructed to receive a fiuid, a source of fluid under pressure, and means for supplying said uid under pressure to said expansible means to actuate the same and dislodge thesaid tray from said surface,

8. In a refrigerator, a, cooling unit provided with a tray compartment having a refrigerated surface, a tray removably disposed on said surface, a hollow expansible member interposed between said tray and said refrigerated surface, a source of iiuid under pressure, and means for injecting said fluid under pressure into said expansible member to effect dislodgment of said tray from said surface.

9. For use in a refrigerator having a cooling unit and a freezing compartment, a tray adapted to be positioned in said freezing compartment and said tray in turn being provided with one or more freezing compartments and a fluid chamber, each of said tray compartments having a flexible wall subject to pressure in said chamber, said tray beinfr also provided with a socket opening into said uid chamber, a source of fluid under pressure, a conduit connecting at one end with such source and at its opposite end` terminating in a nozzle accessible from the exterior of the refrigerator, a normally seated yieldable valve in said nozzle, and means in said socket cooperative with said valve whereby when the tray is brought in a position effecting coopera- 5 tion of said socket with said nozzle the valve is unseated to permit introduction of uid under pressure into said chamber.

10. For use in a refrigerator having a cooling unit and a freezing compartment, a tray adapted to be positioned in said freezing compartment and said tray in turn being provided with one or more freezing compartments and a iiuid pressure chamber, each of said tray compartments having a fiexible Wall subject to pressure in said chamber, said tray being also provided with a socket opening into said pressure chamber, a source of uid under pressure, a conduit communicating with said source and terminating in a nozzle accessible from the exterior of the refrigerator, a normally seated yieldable valve in said nozzle, means in said tray socket cooperative with said valve whereby when the tray is brought into a position effecting cooperation of sald socket with said nozzle the valve is unseated to permit introduction of fluid under pressure into said chamber, said source of fluid including a foot actuated pump.

11. For use in a refrigerator having a cooling unit and a freezing compartment, a tray adapted to be positioned in said freezing compartment and said tray being provided with one or more grid compartments and a fluid pressure com partment, the bottom Walls of said compartments being flexible, a source of fluid under pressure, conduit means extending from said source and terminating in an exteriorly accessible nozzle having a depressible valve member controlling discharge from said nozzle, said tray being provided with a socket in communication with said iiuid pressure compartment and said socket having a valve unseating member disposed therein and arranged so that when the tra-y .is brought into a position effecting cooperation of said socket with said nozzle the Valve is unseated to permit inroduction of iiuid under pressure into said fluid pressure compartment to fiex the bottoms of said grid compartments and dislodge matter therefrom.

LOGAN L. MALLARD. 

